Fire-box.



C. DUCAS.

FIRE BOX.

APPLICATION FILED FEB. 24. 1914.

Patented Mar. 21, 1916.

2 SHEETSSHEET I.

Inventor M M per Attornegs C. DUCAS.

FIRE BOX.

APPLICATION FILED FEB. 24, 1914.

Patented Mar. 21, 1916.

2 SHEETSSHEET 2' Invehbor per Attorneys 9 2 o e owmmwwmwwwm,mbwwmwwmwfiwwwwwmwwwwwm a 1 lm 9. s W WWOQ n gbbnn w 2@Q\\.\\.\ CC .Ow 1 O o 06 o o o o 0 mo 0 o o o n w 0 o o 0 0 o o 0 mo 0o o o 0 w 2 1 o o o 0 01 O3 1 o w 0 0 m 9 0 m 0 a 0 db 1|| hbllbhphm w II I I I I I I I IIWVUGO .LHn f MO Witnesses UNITED' STATES PATENTOFFICE.

CHARLES DUCAS, OF NEW YORK, N. Y., ASSIGNORTO JACOBS-SHUPERT UNITEDSTATES FIRE-IBOX COMPANY, OF NEW YORK, N. Y., A CORPORATION OFYENNSYLVANIA.

FIRE-BOX.

To all whom it may concern Be it known thatI, CHARLES DUCAS, of NewYork, in the county of New York, and in the State of New York, haveinvented a certain new and useful Improvement in Fire-Boxes, and dohereby declare that the following is a full, clear, and exactdescription thereof.

The object of my invention has been to provide a fire-box which, whilestayed with ample rigidity, shall afford access to a man so that he canadequately inspect the inside of the fire-box, and which shall affordrelief for expansion, or either of such advantages without theother,a1'1d to such ends my invention consists in a fire-box hereinafterspecified.

In the accompanying drawingsFigure 1 is a vertical longitudinalsectional view of a fire-box embodying my invention, and Fig. 2 is an.end view thereof, the right side showing a transverse vertical sectionof Fig.

.-1,.taken on the line A-A, of Fig. 1.

:My invention is applicable to any type of fire -;boxes, such, forinstance, as those in which the crown sheet and the wrapper sheet arerespectively formed of a single sheet of metal as well as those in whichsuch sheets are formed of separate sections, and while I haveillustrated the application of my invention to the latter type offire-box, as the best illustration thereof known to me, itis to beunderstood that such illustration is typical only of many possibleembodiments thereof, and my invention is not to be restricted thereto.

The fire-box illustrated in the drawings is essentially that which isthe subject of Patent No. 917,172 to Shupert and Jacobs of April 6,1909, except in so far as changed in accordance with" my invention. Suchfirebox consists of a crown sheet made up of sectionsl, which arecomposed of straight side portions 2, forming the sides of the crownsheet, and in the present instance of a straight horizontal portion 2 onthe top, which is connected by curved portions 3, each section beingU-shaped, the bend of the U 4 being toward-the fire and the flanges 5extending away from the fire. The wrapper sheet also consists ofsections 6, having outwardly extending flanges 7, and the crown sheet isstayed from the wrapper sheet by the use, in the present instance, of

stay sheets 8, which are riveted between the Specification of LettersPatent.

Patented Mar. 21, 1916.

Application filed February 24, 1914. Serial No. 820,452.

flanges 5 of the crown sheet sections, and the flanges 7 of thewrapper-"sheet sections. Said Wrapper sheet sections consist of straightvertical portions 9 on the sides, and, in the "present instance, of astraight horizontal portion 10 on the top, which are connected by curvedportions 11. I have discovered that, if the hips, so to speak, of thewrapper sheet be made in the form of an arc, and particularly an arc ofa circle, that it is sufiiciently self-supporting so that it does notneed to be stayed except at the ends of the arc, and thatthe staying canbe omitted throughout said arc so as to admit the passage of a mansbody. I have, therefore, in the present instance, formed openings 12 inthe stay sheets 8 so that, While the stay sheet extends from a point 14,which is approximately the center of the arc, to the ends of the are (asby the portions marked 15 and 16) the said hip will be sufiicientlystayed so that the openings 12 can be left for the passage of theinspector. This is because the cross-section of a vessel under internalpressure tends to assume the shape of a circle, and, therefore, when aportion of it is made substantially in an arc of a circle, and its endsare stayed, pressure does not tend to change the shape of that portion,and staying is not needed-therefor.

Admission through the back sheet 17 of the boiler into the passage-wayformed by the openings 12 is obtained through a manhole 18 of the usualtype, and closed by the usual cover.

By means of my invention, a man using suiiiciently long handled hammerscan inspect every rivet, seam and surface on the inside of the boiler soas to adequately determine its condition.

My invention, providing as it does, portions of the fire-box which areunstayed and are, therefore, free to change their shape with varyingexpansion, affords relief, from strain due to expansion, while retainingample strength. This feature of my invention may be used without makingthe spaces large enough to admit a man.

It will be seen that my invention is applicable to any portion of afire-box which can be made substantially in the arc of a circle, andwhich is connected with parts not having such a contour.

I claim-- 1. In a fire-box, the combination of an extcrior sheet havingan arched portion connected with portions not arched, and stayingextending from substantially the center of the arch to the springersthereof, the 5 space between said staying and said arch beingsubstantially unobstructed.

' 2. In a fireox, the combination of a crown sheet and a wrapper sheet,said wrapper sheet'having an arched portion connected with unarchedportions and two lines of staying extending from the crown sheet to,

the springers of the arch, the space between- 4. In a, fire-box, thecombination of a.

wagon top wrapper sheet having curved hips and a crownsheet, lines ofstaying conmeeting the crown-sheet with thewrapper sheet at each side ofeach curve of each hip of, the wrapper sheet, said lines of stayingbeingsufliciently separated, and the space between themsufiicientlfunobstructed to -.permit the passage of arnans' body.-

crown sheet. formed oftran sverse sections, a wagontop wrapper sheet andstayingconnecti'n'g said crown sheetjwith saidwrappersheet, there beingseparate lines of staying extendingftoeach end, of-each curve on thehips ofthe wrapper sheet. and the space between said lines of staying ateach-.hipbein'g unobstrueted.

In a .fi1'e-box., the combination of. a

I a wagon top. wrapper sheet and stayingfconmeeting. said crown-sheetwith said wrapper, sheet, therebelng separated l nes ofstaymg extendingto each end of each curve. on the hipof the w 'apper sheet. and thespace he tween said lines of staying at each hipbeing 5.: 'In' a..fire-.box,- the combination of. a

crown sheet formed of transverse sections,

unobstructed, and a "inanhole in the back sheet oi: the hre box in linewith the openings thus formed.

7. In a fire-box,' the combination of a crown sheet and a. wrappersheet, cach oi. which is formed of transverse sections, said wrappersheet having curved hips, a line oi staying connecting each end of thecurve of each hip withthecrown sheet, the space between the lines ofstaying at each hip being unobstructed.

8. In a fire-box, the'co'mbination of a crown sheet and a wrapper sheet,each of which is formed of transverse sections, said wrapper, sheethaving curved hips,a line. of

staying connecting each end of the curve of each hip with the crownsheet, the space between the hnes'ot staying at each hip bemgunobstructed, and manholes 1n. the back sheet of the fire-box in linewith theopenings thus formed.

9. In a fire-box, the combination of a crown sheet and a wrapper sheet,each formed of transverse sections havingoub.

wardly projecting flanges, and stayshceis secured between saidflanges,said. wrapper sheet having curved hips and said stay sheets beingcut-away beneath said hips sulli- .ciently to afford passage fora n ians body.

10. In a fire-box the. combination oi'fa crown sheet and a wrappersheet. caoh' formed of transyerse sections having outwardlyprmectmgfiangcs, and stay sheets secured between said flanges, saidwrapper sheet having cur\'ed hips and said stay sheets being cutawavbeneath said hips sulli-1 cieutly to afford passage for aiuaifislboily,

saidcutaway portions. I

In testimony that I claim the ,and inn nholesin the back sheetsoppositev have hereunto set my hand. I

" CHARLES DUCAS.

foregoing Witnesses: H,

EDWIN J. PRISDLE, L. BRODEBICK.

